Workbench #12: Laminating the Top

The time has come to start making this thing look like a bench. In order to make the short stretchers I need to know what the final width of the bench is going to be. I am mostly playing the length, width, and thickness of the top by ear since I didn’t know how much I was going to have to remove from the construction grade wood I used. I purchased the pieces for the top 1 year ago so they have had quite a bit of time to dry out as well as bend and twist and warp. There are also some very large resin pockets in the wood and they make a mess of all my tools. I really can’t wait until this project is finished so I can clean all my tools!

My plan for the top was to glue up all 8 pieces for the top into groups of two, then glue up those 4 groups into groups of 4, and then glue those 2 groups of 4 into a single top. After going through all the pieces and trying to select which faces would become the top and which piece I wanted to be the front, it was time to start the task of jointing and planing the pieces and starting the laminations.

Jointing pieces this big and heavy was an interesting experience. I tried a few different methods and I just wasn’t able to get the pieces straight. I came very close, however, there was always some bow in the pieces. I was able to do a decent job of getting the 4 faces square and the pieces were a constant width and thickness but I could not get them straight. When I glued the pieces together I arranged them so the gap caused by the bowing was in the middle. This will tend to keep the ends of the top in close contact as the top ages.

The glue up was rather straightforward although I did have to go get some more clamps. The boards are 10 feet long and I wanted to make sure I had a clamp at least every foot and closer than that if possible.

I eventually ended up with 4 groups of 2 pieces laminated together:

I jointed and planed these since it was the last time I would be able to fit them on my 6” jointer. I was trying to minimize the amount of hand work I was going to have to do later, which worked, except I think I ended up taking off more thickness than I really needed to. The pieces started off at about 5.5” and my final top looks like it is going to be about 4.75” thick. Now, some of the boards bowed quite a bit and that is part of the reason for the top being thinner than desired but part of it was that I did a poor job of keeping the pieces aligned when doing the glue up. Needless to say that running the boards that are now twice as heavy across the jointer was even more challenging than before and I had the same problem getting the pieces straight. There was a slight bow left over when I was done.

Now I could glue up the smaller sections into 2 groups of 4:

Now, at this point the two halves of the top would still fit through my thickness planer but not across my jointer so I needed to do some cleanup of the bottom face by hand so I could have the planer clean up the top face:

Before running the top through the planer I decided to try to fill in some of the checks that developed at the boards dried out and I also wanted to fill in the knots so they would be more stable. This is the same thing I did for the legs and the stretchers:

The 4 piece subassemblies were just about the limit of what I could safely lift by myself. I am going to have to find some help when I finally glue the two pieces into a single top:

All in all the laminating went as good as I could have hoped and my final thickness, while not as thick as the design called for, is still plenty thick enough to be both thick and heavy. One reason I was shooting for 5 inches thick was to ensure that there would be enough mass that the bench wouldn’t scoot around while planing. I don’t think I am going to have problems with that even at “only” 4.75 inches. I also didn’t lose as much length to checking as I thought I might so I am going to adjust the design slightly to add another foot or so to the length of the bench. This will get it up around 9 feet long!

The next step is to make the short stretchers, now that I know how wide the top will be, and to start marking the top for the leg mortises. I think I am going to peg the two halves of the top so I can mark everything but then still have the two halves separate to cut the mortises and probably install the tail vise. I think having the pieces separate will make handling them a lot easier in order to do all the work on them. I won’t really be able to move the top around once it is a single piece. This is still a theory so I might decide that the risk of the two halves not going together in exactly the right spot won’t be worth making it easier to work with.